Air filter



Aug. 1e, 1927.

o. v. GREENE AIR FILTER Filed April s. 1925 2 Sheets-Sheet l ff El I O5 ca z' V @ree/fe O. V. GREENE Aug. 16, 1927.

AIR FILTER Filed April 5, 1925 2 Sheets-Sheet '2 ffy, /5

INVENTOR. E.' z'egzfe O6 caff ATTORNEY Petenfe'el Aug. 1c, 1927. l

UNITED sra-TissV PATENT OFFICE.

f OSCAR V.GREENE, F CLEVELAND, OHIO.

In FILTER.

Application led April 3, 1925. Serial-No. 20,400.

v yfiltering element consisting of a series of sheets of vscreen material wound into a cylin- V der. -The presentv linvention then relates to f1,- the particular construction and the arrange ment of parts for mounting the unit, the dei '15 vice being so made that the filtering element is easily removable for cleaning and the like. .To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described and particularly pointed out in the claims. The annexed drawings and the following description set forth in detail certain mechanism embodying the invention, such disclosed means constituting, however, but one of various mechanical forms in which the principle of the invention may be used.

In sai/. annexed drawings Fig. 1 is an elevational view-showing the device mounted'on a carburetor; Fig. 2 is an elevational view of the vdevice itself; Fig. 3 is a central vertical section through the device; Fig. 4 is a bottom plan view of the r filter element removed from the holding member; Fig. 5 is a perspective view of the handle; Fig. 6 is a plan view of the screen sheetfrom whichv the filtering element is formed; Fig. 7 is a plan'view of the filtering sheets with the corrugated screen sheet mounted thereon; Fig-8 1s a' diagrammatic section on the line 8-8 of Fig. Figs. 9 and 10 are diagrammatic sectional views on the lines 9-9 and 10-10 respectively of Fig. 6; Fig. 11 isa broken diagrammatic view showing the method of rolling the element; Fig. 12 is a sectional view slmilar to Fig. 3 showing a modified construction; Fig. 13 is a plan view of the layer of material with the compensating sheets in place; and

Figs. 14 and 15 ,are sectional views ony the lines 14-14 and 15-15, respectively, of F ig.l 12.-

` The present air filter for use on internal combustion engines or for any relatively small volume air stream consists of a" bottom holding member 1 formed as shownin the shape of a shallow vcup or a disk"v 2 with al flange 3 around the edge, the disk having a' central opening `4 anda flangeor securing,

pipe 5 for attachment to the air intalie pipe 4 6 of a carburetor 7 or the like,A

The ilterin element consists of cylinder 8 of ltering material, provided at' the top with a cover 9 having a knob orl I I handle 11. yThe filtering element is formed by rolling a layer 12 'of filtering material with a layer 15 of corrugated filtering material intoa cylinder. Y

As best shown in Figs. 6 to 10, the layer 12 consists of a strip of screen cloth,13

folded lengthwise and having another strip e' honew 14 of screen mounted between the folde portions of the strip 13, the wires Aof the strip on the bias sothat when'folded, the wires in l 14 being enguierly disposed relative to the.

wires in the strip v13. vThe stripl is cut ,75 u

the portion 13b as is'clearly indicated on .j 6. The strip 14 is longer than the strip 13l and has its edges folded or doubledas at 16.' l' The corrugated .strip 15 of screen cloth folded in edges 2l 'is preferably having rolled up in conjuction with the layer 12,

such layer being placed .on the layer 12 as .f

indicated in 8 andv then rolled togetherl as indicated in Fig. 11 so asto form a com.- '35 plete revolution ofthe layer 12 on thein-m side of the cylinder and the extending'vend 22 of the strip 14 is of a len h toI .form a complete revolution around t e outside of the cylinder. In the form as showni there are in 'the nished element four revo utions 'of the layer 12 and three sp'ac revolutionsof the corrugated strip 13, and t inner and outer ends ofthe layer 12 overlap a8 indicated in Fig.' 4.

The cylinder is held in its" rolled position by screws 25 which are threaded through the cylinder and such screws form their own threaded openings in the screen and securely tie -the rolled cylinder in the desired position.

To hold the cover to the cylinder, abraclret 30, preferably V-shaped, is employed which has its open ends 31 bent to lie dat against the inner cylinder wall and which has a at portion 32 at the top on a level with the edges of the screen. This bracket has apertures formed in the ends 31 into which screws 33 4pass land these screws have threaded en'- gagemetin `such apertures, thus securing the cylinder and bracket together.v Thecover has a central opening 35 and two or more indentations orl holes 36and a screwl is passed through an aperture 37 in the vfiat portion 32 ofthe bracket and through the-cover aperture 35 and has threaded enagement withthe tapped aperture 38 in the nob. The knob on its lower face is formed with oneor more lugs or prongs 39 which fit into the indentations 36 of the cover,thus

' preventing ,relative rotation between the '.-cover and the knob when the screw 40 has ybeen tightened. l AThe bottom edges of the cylinder as shown in Figs. 3,-9 and 10 present folded edges of the several strips of screen used and the raw edges are enclosed by the cover, thus eliminating sharp points and the likelihood of thev operator being scratched or injured in handling and Vremoving the element lfrom i the holding member, such folded edges also prevent ravelling o f the screens.

The cylinder preferably has a ti ht fit in the holdingv member but any suita 'le securin devices may be employed to prevent the e ement from 'jarring'loose and in the v)form shown, this holding device consists'of a pair of spring clips which arel loosely attached to the holding member by a pair of rivets 46, the upper ends being adapted to snap over a rib 47 formed around the 'cover. These spring clips are preferably bent'to form a V-shaped member through- 'out their extent past the filtering element so as to reduce to a minimum their tendency to lblock a portion of the filtering element `and they are flat at the bottom and4 atthe top where the rebent rtions 48 can Abe snapped over the rib 4 so as to hold the filtering element and cover securely on the holding member. The loose rivets allow the spring cli s sulicient movement outwardly from the ltering element so that when theyl are released from engagement with the cover, the cover and filtering element may easily be withdrawn.

In thefform shown in Figs. 12 and 13, the filtering element is provided with compensating devices so as to allow the air currents pulled through the filtering screens to enter substantial-1y equally over ythe entire area of the element. It is of vcourse known that in a device as shown, the air current will tend to pass through the bottom of the ,ele-

.ment nearest the opening in the holding member in greater quantity and at higher velocity thanthrough the upper portion of the element and therefore in the construction shown in Fig. 12, a sheet 60 of compensating screen is employed which, when the element 1S rolled up, give a series (if-single revolutions of extra screen material of .l

varying heights. As shown, this compensating sheet is so made that `when the elementis rolled up, there will be a layer of the compensating sheet forming a single `revolution 61 in the first revolution of the layer and this first compensating revolution extends only7 a limited distance up the wall of the element. The second portion 62 of the compensating element makes also a sin le revolution and extends upwardly7 in thee ement a greater distance than the first and the third portirin 63 of the compensating sheet makes a complete revolution in the filtering element and extends higher' than the second Acompensating element. Thus in the finished structure, the filtering element "f has its greatest densityrnear the bottom or outlet end of the device and this density decreases tovvard the top'of the filtering element, thus giving an increased resistance from the top of the element to the bottom v thereof so as to forcethe air equally through' the element at all times. This compensating means is similar to that shown in my -zopending ap licationfiled March 27, 1926, Serial N umiier 18,768, in which compensating devices are shown for the filter element where the element is larranged as substantiallya rectangular unit.

Invusing the present air cleaners for internal combustion engines, it lis preferable to remove thelter proper from theholding member and to dip the same in oil so as to coat the wires of the various sheets of screen material which aids in filtering thtl air.. The number of revolutions of the filtering vmaterial, the size of screen mesh employed stated means be employed.

I therefore particularly point outv and distinctly claim as my invention 1. A filter element consisting of a sheet of screen rolled to form avhollow cylinder and provided with a cover at one end, said filtering cylinder increasing in density :from such cover end to the other.

2. A ltering element consisting of a hollow cylinder of screen, said cylinder consisting of a layer of lflat screen and a sheet of corrugatedscreen rolled into shape and pro lowing claims or the equivalenty of such vided with compensating screenI adapted to increase the density of said element'from one end to the other.

. 3. A filter element consisting of a hollow.-

cylinder of woven wire screen, comprisinga layer of flat screen `and a shorter length of corrugated screen. placed in juxtaposition and rolled together into such cylinder and providin therein a series of spaced revolutions of ltering screens, a cover for one end of said cylinder having' al handle, and a re l movable holding memberfor''the yother'end n' of saidy cylinder.

4. Ak'lter element consisting lofafhollow cylinder' of woven wire screen, comprising a .t layer of screen and a' shorter' length'of corrugated screen placed inijuxta osition and rolledv together into such cylin er and providing therein a series ot' spaced revolutions of ilteringscreens, a cover for one end of said cylinder havin a handle, and means mounted on said hol ing member and adapt ed for removable engagement with ysaid .membenv cover Vfor securing said *element lon said 5. A lilter element consisting Aof a hollow cylinder of woven wire screen, com rising a layer of screen and -a shorter lengt of corrugated screen placed in juxtaposition and rolled together into such cylinder andv roviding therein a series of spaced revolutions of filtering screens, a cover for one end of said cylinder having a handle, means for attaching said cover to said cylinder, consist-4 ing of a bracket mounted interiorly of 'said cylinder adapted to be secured to the walls thereof, and means for attaching saidbracket to said cover.

6. A lilter element consisting of a hollow cylinder of woven wire screen, comprising a layer of screen and a shorter length of `cor rugated screen placed in juxta osition and rolled together into such cylin er and providing therein a series of spaced revolutions of filtering screens, a bracket mounted `in said cylinder and securedfthereto and havin a portion ilush with one edge of said cylin er, a cover mounted on the end of said cylinder, end ineans securing said cover to said bracket. y

7. A filter element consisting of a hollow cylinder of woven Wire screen, com rising a layer of screen and a shorter lengt of corrugated screen placed injuxtaposition and rolled together into such cylinder and providing therein aseries of spaced revolutions of filtering screens, a bracket mounted in said cylinder and secured thereto and havlng a portion fiush'with one edge of said cy inder, said portion having an aperture, a cover mounted over the endofsaid cylinder and having an aperture, a handle mounted on the outside of said vcover,land' a holding screw'passing through said bracket and cover and engaging said handle to clamp said coverY to said bracket and said handle to said cover. 8. A lter element consisting of a hollow cylinder of woven wire screen, comprising a layer of screen and-a shorter length' ofv cor-v rugated screen placed in juxta osition and rolled together into such cyli'n er and roviding therein 'aseries of spaced revolutions of filtering screens, a bracket mounted in said cylinder and secured thereto and hav-v ing aportion flush with one vedge of'said cylinder, said portion havingcover mounted -ojver the en of'saidfcylinder and having an ,aperture, a handleinounted 'ontlie "outside of 'said'coveig a holding screw passing through-,saidbracket and cover and engaging said handle to clamp saidr cover to said bracket andk said handletosa-id cover, and interengaging means on said handle and cover and preventing rotation of said handle when in its clamped osi'tion.

9. `A cylindrical an aperture, a

tei' element consisting ACl A .ISO

of a relatively long la v'er of flat woven wire screen, a shorter lengt of corrufatedwoven yWire screen adjacent thereto, said two layers being rolled together to 'form a hollow cylinder with lthe corrugated screen between the flatscreen leaving a complete revolution of the straight screen on both the inside and the outside of the cylinder.

10. A c lindrical filter element consisting of a vrelatively long layer of flat woven wire screen,.a shorter length of corrugated woven wire screen adjacent thereto, said two layers being rolled together -to form a 4hollow cylinder with the corrugated screen between.

the flat screen leaving a completerevolution of the straight screen on both the inside .and the outside of the cylinder, one edge of inner layers thereof.

13. A filter element consisting of. layers i of spaced, foraminous sheets formed into a hollow' cylinder, said ilteringelement' in-v creasing in density from one end of said i cylinder to the other.

l 14. Al filter element consisting of a sheet of foraininous material rolled to form a hollow c linder and having a cover at one end, s 'aid d, from Such cover end to the other.

`15. A filter element consistin of a' hollow cylinderof foraminous materia said cylinyi'er consisting of a'layer of a lflat forai'ninous ysheet and a corrugated foraminous sheet ltering cylinder increasing in density ico' said element being of less density than the 15 il. l i 1,eso,ia'n

'rolled into shape and provided with a. com- 'rst strip and having its wires angulerl rel pensating sheet rolled therein and adsfted lated to the wires of said first stri ,sai two yto increase the density of said cylinder rdm strips being rolled to form `a ho ow cylin- 10 one end 'to the other. Y Ader of several layers.

"6 16. A filter element'comprsihg a strip of Signed by me this 31st day of March,

woven wire screen, asecond stri of woven 1925.

wire screen placed in juxtapositnon to said OSCAR V. GREENE. i 

